On the flip side you  increase your equity, which decreases your risk of being  upside down in the event of market correction.

From my research you basically appear in front of a code enforcement hearing board and pray they accept to decrease the total lien amount or forgive it... however its entirely up to the board (atleast in Miami).I've talked to my lawyer and he stated the same thing however I've been hearing alot of local investors talk about forgiveness from the enforcement boards. 

Paying down a mortgage decreases cash flow it does not increase it due to the lost opportunity value of cash.

Everyone else's recommendations of sloping the earth next to your walls away from the house (can be accomplished with flower beds near the walls - avoid plants w/ long roots like trees), adding/fixing gutters, extending roof overhangs, and subterranean drainage are all steps to take to decrease water infiltration.Nowadays we ideally insulate and waterproof our basements from the outside - but that's more work than it's worth for a flip.

OR if I got short term financing for 6 months to increase income/decrease expenses and get a better value which makes a refinance possible.

My entire credit history consists of one card I've held for nine years and a second I just opened earlier this month to increase my open lines and decrease my overall utilization percentage hopefully kicking that score closer to 800 once a few payments are reported. 

However, there are many cons which make me concerned:Philadelphia, PA: population growth rate is slowing down, high crime rates, low median household income, etc.Baltimore, MD: the population is decreasing fast, high crime rates, negative home appreciation the last 10 years, etc.I have a saving about 100K - 150K to invest.

Also it decreases (albeit only slightly) the magnification of the power of leverage.  

We saw that quite often ourselves where a home would list for something like $475,000 and first price drop would be $25K then another $10K a few weeks later (and then even more price decreases depending on how far out of whack things are).  

If all your rentals in the same city, you might not pay any taxes - new properties usually drive your profit down because of current expenses (not depreciable) which is not included in the cost of the house.Another way to "decrease" your taxable income is to pay yourself a salary but then this income will get more taxes - SS, for example, which you don't pay on your sch.E income.Make a spreadsheet in Excel and put your numbers all way through including income taxes and see your cash flow model.Still better than working for W-2: it's your money making you more money.